1. Field of the Invention
The present invention relates to devices or methods used in tissue repair, more particularly, devices and methods for attachment of biological tissue (i.e., tendons or ligaments) to a bone mass.
2. Description of the Related Art
Soft tissues, such as tendons and ligaments, generally are attached to bone by small collageaous fibers. These connections are strong but permit the tendons and ligaments to be flexible. When a tissue, or a portion of a tissue, is torn away from the bone and requires repair, a surgeon is often required to repair the detached soft tissue with sutures, which are passed through bone tunnels and tied. A number of devices have been developed for securing a ligament or tendon to a bone mass. These devices can be used in place of bone tunneling techniques. These attachment devices are usually anchor element through extensive surgical incisions and, in some circumstances, by arthroscopic surgical techniques. The placement of bone tunnels for repair can be difficult and generally require large open incisions. Recently, through the advent of arthroscopic surgery, where the surgeon looks into a joint cavity with an arthroscope, there has been a trend to repair soft tissues back to bone through small incisions called portals. The unique free loop knotless suture anchor assemblies described herein facilitate this difficult and precise procedure.
A variety of devices are available for attaching objects to bone, such as screws, staples, cement, suture anchors, and sutures alone. These devices have been used to attach soft tissue, such as ligaments, tendons, muscles, as well as objects such as prostheses, to bone. A suture anchor assembly is a device, which utilizes small anchors with suture materials attached thereto. A device, such as a screw, is inserted into the bone mass and anchored in place. After insertion of the anchor, the attached suture is passed through the tissue to be repaired. The tying of a knot in the suture is then required to secure the tissue to the bone. The process of passing the anchored suture through the soft tissue and tying a knot is time consuming and difficult to undertake in the tight space encountered during arthroscopic surgery and sometimes even in conventional open surgery.
Knotless anchor assemblies have been popular and are embodied in a number of prior patents such as U.S. Pat. No. 6,045,574 wherein there is provided an assembly with an anchor means having a snag means, and a hollow sleeve element with a loop suture element attached thereto, wherein the snag means captures a loop suture element of the hollow sleeve element to draw tissue into secure attachment with a bone mass.
However, difficulties still exist and the present invention attempts to address these with a method and apparatus for knotless suture anchoring.